Whisk together marshmallow fluff, sweetened condensed milk, lime juice and zest in a medium bowl until combined.
In a large mixing bowl, beat heavy cream until stiff peaks form.
Fold whipped cream into marshmallow mixture.
Cover and chill for at least an hour and up to 24 hours.
Top with additional lime zest prior to serving.
Serve with strawberries, pineapple, graham, crackers, nilla wafers, animal crackers.
